U.S. patent application number 15/511500 was filed with the patent office on 2017-10-05 for composition for thermal storage and heat transfer applications.
The applicant listed for this patent is HINDUSTAN PETROLEUM CORPORATION LTD.. Invention is credited to Nettem Venkateswarlu Choudary, Kandoth Madathil Pramod, Kanaparthi Ramesh, Peddy Venkat Chalapathi Rao.
Application Number | 20170283676 15/511500 |
Document ID | / |
Family ID | 56555517 |
Filed Date | 2017-10-05 |
United States Patent
Application |
20170283676 |
Kind Code |
A1 |
Pramod; Kandoth Madathil ;
et al. |
October 5, 2017 |
COMPOSITION FOR THERMAL STORAGE AND HEAT TRANSFER APPLICATIONS
Abstract
In accordance with the present subject matter there is provided
a composition including at least one nanoparticle, at least one
alkali metal salt and a metal salt having water of crystallization.
The subject matter also relates to a method for preparation of the
composition.
Inventors: |
Pramod; Kandoth Madathil;
(Bangalore, IN) ; Ramesh; Kanaparthi; (Bangalore,
IN) ; Rao; Peddy Venkat Chalapathi; (Bangalore,
IN) ; Choudary; Nettem Venkateswarlu; (Bangalore,
IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HINDUSTAN PETROLEUM CORPORATION LTD. |
Mumbai |
|
IN |
|
|
Family ID: |
56555517 |
Appl. No.: |
15/511500 |
Filed: |
June 17, 2016 |
PCT Filed: |
June 17, 2016 |
PCT NO: |
PCT/IN2016/050188 |
371 Date: |
March 15, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F24S 80/20 20180501;
C09K 5/12 20130101; C09K 5/063 20130101; Y02E 10/40 20130101 |
International
Class: |
C09K 5/12 20060101
C09K005/12 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 19, 2015 |
IN |
2352/MUM/2015 |
Claims
1. A method for preparation of a composition, the method
comprising: a) contacting at least one nanoparticle with at least
one alkali metal salt and a metal salt having water of
crystallization to obtain a mixture; b) subjecting the mixture to a
temperature in the range of 100 to 200.degree. C. in a closed
system to obtain dispersed nanoparticles in a mixture of salts; and
c) removing water from the dispersed nanoparticles in a mixture of
salts to obtain the composition.
2. The method as claimed in claim 1, wherein the at least one
nanoparticle is selected from the group consisting of molybdenum
disulfide, cupric oxide, carbon nanotube, functionalized carbon
nanotube, multi-walled carbon nanotube, activated carbon, activated
carbon sphere, graphene, and combinations thereof.
3. The method as claimed in claim 1, wherein the at least one
nanoparticle weight percentage in the composition is in the range
of 0.01 to 2%.
4. The method as claimed in claim 1, wherein the at least one
nanoparticle has a particle size in the range of 30 to 500 nm.
5. The method as claimed in claim 1, wherein the at least one
alkali metal salt is selected from the group consisting of sodium
metal salt, lithium metal salt, potassium metal salt, and
combinations thereof wherein, the at least one alkali metal salt is
inorganic anions.
6. The method as claimed in claim 1, wherein the at least one
alkali metal salt weight percentage in the composition is in the
range of 5 to 90%.
7. The method as claimed in claim 1, wherein the at least one
alkali metal salt is a combination of lithium and potassium nitrate
wherein potassium nitrate weight percentage in the composition is
in the range of 60 to 70% and lithium nitrate weight percentage in
the composition is in the range of 5 to 20%.
8. The method as claimed in claim 1, wherein the metal salt having
water of crystallization is selected from the group consisting of
alkali metal salt, alkaline earth metal salt, and transition metal
salt.
9. The method as claimed in claim 1, wherein the metal salt having
water of crystallization has melting point in the range 40 to
120.degree. C.
10. The method as claimed in claim 1, wherein the metal salt weight
percentage in the composition is in the range of 10 to 35%.
11. The method as claimed in claim 1, wherein the metal salt is
hydrated calcium nitrate.
12. The method as claimed in claim 1, wherein the composition has
moisture content in the range 3 to 13%, and has a melting
temperature in the range of 100 to 150.degree. C.
13. The method as claimed in claim 1, wherein the mixture of salts
containing dispersed nanoparticles is subjected to a temperature of
100 to 200.degree. C. for 0.5 to 2 hours.
14. A composition comprising of (a) at least one nanoparticle
having particle size in the range of 30 to 500 nm (b) at least one
alkali metal salt; and (c) a metal salt having water of
crystallization, wherein the composition has a melting temperature
in the range of 100 to 150.degree. C.
15. The composition as claimed in claim 14, wherein the at least
one nanoparticle is selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, and graphene.
16. The composition as claimed in claim 14, wherein the at least
one nanoparticle weight percentage in the composition is in the
range of 0.01 to 2%.
17. (canceled)
18. The composition as claimed in claim 14, wherein the at least
one alkali metal salt is a combination of lithium and potassium
nitrate wherein potassium nitrate weight percentage in the
composition is in the range of 60 to 70% and lithium nitrate weight
percentage in the composition is in the range of 5 to 20%.
19. The composition as claimed in claim 14, wherein the metal salt
weight percentage in the composition is in the range of 10 to
35%.
20. The composition as claimed in claim 14, wherein the metal salt
is hydrated calcium nitrate.
21. The composition as claimed in claim 14, for use in solar
thermal energy storage.
Description
TECHNICAL FIELD
[0001] The subject matter described herein in general relates to a
composition comprising at least one nanoparticle, at least one
alkali metal salt and a metal salt having water of crystallization.
The subject matter also relates to a method for preparation of the
composition. The composition can be used in concentrated solar
power (CSP) plant as solar thermal energy storage materials as well
as heat transfer fluids.
BACKGROUND
[0002] Global warming is one of the major current environmental
issues, which is caused by release of greenhouse gases in the
environment. Increased consumption of energy from conventional
fossil fuels in the last decades has led to the release of
greenhouse gases which could adversely affect the climate. To
reduce the impact of climate change due to global warming, current
energy research is intensively focusing towards the effective
utilization of most abundant energy source available, nothing but
solar energy to save the environment from green-house producing
fossil fuels and also to provide energy security. Considering solar
energy, no investment is required for the source and the main cost
is related with the thermal storage system for storing solar
thermal energy for sufficient time period.
[0003] Solar thermal energy storage is a key element for the
improvisation of the efficiency of thermal energy utilization
because large scale solar energy production demands a wider storage
capacity. High temperature thermal energy storage systems can deal
with a wide range of temperatures and concentrated solar power
(CSPs) applications and have greater potential in terms of
technology as well as economy. The solar thermal energy can be
stored in the molten salt media from where the heat energy is
transferred to water for thermal operations such as high-power
steam generation in solar power plants.
[0004] Fazel Yavari et al (Journal of Physical Chemistry C; 2011,
115, 8753-8758) have reported thermal conductivity enhancement of
organic phase change materials by the addition of graphene
nanoparticles. Donghyun Shin et al. reported (International Journal
of Heat and Mass Transfer; 2014, 74 210-214) specific heat capacity
enhancement of lithium carbonate-potassium carbonate salt eutectic
by the addition of alumina nanoparticles. In this paper the authors
initially made salt eutectic and added nanoparticle externally and
add extra water and sonicated for 200 minute and finally evaporated
the water to form salt-nanofluid. This consists of multiple steps
and takes more time for the synthesis.
[0005] US20140084205 discloses an invention of nanoparticle coated
phase change material as heat transfer and heat storage
applications. The aforementioned document specifically discloses
Sn/SiO.sub.2 incorporated phase change material to enhance the
thermal conductivity of organic heat transfer fluid.
SUMMARY
[0006] The present disclosure relates to a method for preparation
of a composition, the method comprising the steps of (a) contacting
at least one nanoparticle with at least one alkali metal salt and a
metal salt having water of crystallization to obtain a mixture; (b)
subjecting the mixture to a temperature in the range of
100-200.degree. C. in a closed system to obtain a mixture of salts
containing dispersed nanoparticles; and (c) removing water from the
mixture of salts containing dispersed nanoparticles to obtain the
composition. The present disclosure relates to a composition
comprising of (a) at least one nanoparticle (b) at least one alkali
metal salt; and (c) a metal salt having water of crystallization,
wherein the composition has a melting temperature in the range of
100-150.degree. C.
[0007] These and other features, aspects and advantages of the
present subject matter will be better understood with reference to
the following description and appended claims This summary is
provided to introduce a selection of concepts in a simplified form.
This summary is not intended to identify key features or essential
features of the claimed subject matter, nor is it intended to be
used to limit the scope of the claimed subject matter.
BRIEF DESCRIPTION OF DRAWINGS
[0008] The detailed description is described with reference to the
accompanying figures. In the figures, the left-most digit(s) of a
reference number identifies the figure in which the reference
number first appears. The same numbers are used throughout the
drawings to reference like features and components.
[0009] FIG. 1 depicts scanning electron microscopy (SEM) images of
HPHTF-A and nanoparticle incorporated salt in different
compositions.
[0010] FIG. 2 depicts thermogravimetric curve analysis (TGA) and
differential scanning calorimetry (DSC) of MoS.sub.2 nanoparticle
under nitrogen atmosphere.
[0011] FIG. 3 depicts carbon-sulfur analysis plot of synthesized
molybdenum disulfide (MoS.sub.2) nanoparticles.
[0012] FIG. 4 depicts TGA and DSC of Cupric oxide (CuO)
nanoparticle under nitrogen atmosphere.
[0013] FIG. 5 depicts TGA and DSC of carbon nanotube (CNT)
nanoparticle under nitrogen atmosphere.
[0014] FIG. 6 depicts TGA and DSC of HPHTF-A+0.5 wt % MoS.sub.2
under nitrogen atmosphere and Air atmosphere.
[0015] FIG. 7 depicts TGA and DSC of HPHTF-A+1.0 wt % MoS.sub.2
under nitrogen atmosphere and Air atmosphere.
[0016] FIG. 8 depicts TGA and DSC of HPHTF-A+2.0 wt % MoS.sub.2
under nitrogen atmosphere and Air atmosphere.
DETAILED DESCRIPTION
[0017] Those skilled in the art will be aware that the present
disclosure is subject to variations and modifications other than
those specifically described. It is to be understood that the
present disclosure includes all such variations and modifications.
The disclosure also includes all such steps, features, compositions
and compounds referred to or indicated in this specification,
individually or collectively and any and all combinations of any or
more of such steps or features.
Definitions
[0018] For convenience, before further description of the present
disclosure, certain terms employed in the specification, and
examples are collected here. These definitions should be read in
the light of the remainder of the disclosure and understood as by a
person of skill in the art. The terms used herein have the meanings
recognized and known to those of skill in the art, however, for
convenience and completeness, particular terms and their meanings
are set forth below.
[0019] The articles "a", "an" and "the" are used to refer to one or
to more than one (i.e., to at least one) of the grammatical object
of the article.
[0020] The terms "comprise" and "comprising" are used in the
inclusive, open sense, meaning that additional elements may be
included. Throughout this specification, unless the context
requires otherwise the word "comprise", and variations, such as
"comprises" and "comprising", will be understood to imply the
inclusion of a stated element or step or group of element or steps
but not the exclusion of any other element or step or group of
element or steps.
[0021] The term "including" is used to mean "including but not
limited to". "Including" and "including but not limited to" are
used interchangeably.
[0022] The term "water of crystallization" or "water of hydration"
refers to water that occurs inside the crystals.
[0023] The term "HPHTF" is Hindustan Petroleum High Temperature
Fluid.
[0024] Ratios, concentrations, amounts, and other numerical data
may be presented herein in a range format. It is to be understood
that such range format is used merely for convenience and brevity
and should be interpreted flexibly to include not only the
numerical values explicitly recited as the limits of the range, but
also to include all the individual numerical values or sub-ranges
encompassed within that range as if each numerical value and
sub-range is explicitly recited. For example, a temperature range
of about 100.degree. C. to about 200.degree. C. should be
interpreted to include not only the explicitly recited limits of
about 100.degree. C. to about 200.degree. C., but also to include
sub-ranges, such as 105.degree. C. to 115.degree. C., 150.degree.
C. to 170.degree. C., and so forth, as well as individual amounts,
including fractional amounts, within the specified ranges, such as
100.2.degree. C., 101.6.degree. C., and 102.3.degree. C., for
example.
[0025] The present disclosure provides a cost-effective preparation
method of nanoparticles dispersed in molten salt mixture for
thermal energy storage such as solar thermal applications that can
be used in concentrated solar power (CSP) plant as solar thermal
energy storage materials as well as heat transfer fluids. For solar
thermal energy storage materials, the important materials
requirements are high energy density, high heat transfer
efficiency, good thermal stability, good cycle stability,
non-corrosive behaviour, non-toxic, availability and
cost-effectiveness. The present disclosure relates to a method for
preparation of a composition, method comprising the steps of (a)
contacting at least one nanoparticle with at least one alkali metal
salt and a metal salt having water of crystallization to obtain a
mixture; (b) subjecting the mixture to a temperature of in the
range of 100-200.degree. C. in a closed system to obtain a mixture
of salts containing dispersed nanoparticles; and (c) removing water
from the mixture of salts containing dispersed nanoparticles to
obtain the composition. The method for preparation of the
composition is cost effective. Molten salt based thermal energy
storage received much attention due to the availability and low
cost of molten salt, high thermal stability and thermal
conductivity compared to the organic based thermal storage fluids,
low viscosity at high temperature etc. Moderate thermal
conductivity and low specific heat capacity of molten salts are
enhanced by the addition of metallic and non-metallic
nanoparticles.
[0026] The composition of the present disclosure have melting point
less than 150.degree. C. and thermal stability above 500.degree. C.
without compromising the thermo-physical properties like thermal
conductivity, specific heat capacity and flow properties in molten
state. The present disclosure relates to a composition comprising
of (a) at least one nanoparticle; (b) at least one alkali metal
salt; and (c) a metal salt having water of crystallization, wherein
the composition has a melting temperature in the range of 100
to150.degree. C.
[0027] In one implementation, the composition includes: (a) at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof; (b) at
least one alkali metal salt; and (c) a metal salt having water of
crystallization, wherein the composition has a melting temperature
in the range of 100 to150.degree. C.
[0028] In one implementation, the composition includes: (a) 0.01 to
2 wt % at least one nanoparticle selected from the group consisting
of molybdenum disulfide, cupric oxide, carbon nanotube,
functionalized carbon nanotube, multi-walled carbon nanotube,
activated carbon, activated carbon sphere, graphene, and
combinations thereof; (b) at least one alkali metal salt; and (c) a
metal salt having water of crystallization, wherein the composition
has a melting temperature in the range of 100 to150.degree. C.
[0029] In one implementation, the composition includes: (a) at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof,
wherein the at least one nanoparticle has a particle size in the
range of 30 to 500 nm: (b) at least one alkali metal salt; and (c)
a metal salt having water of crystallization, wherein the
composition has a melting temperature in the range of 100 to
150.degree. C.
[0030] In one implementation, the composition includes: (a) 0.01 to
2 wt % at least one nanoparticle selected from the group consisting
of molybdenum disulfide, cupric oxide, carbon nanotube,
functionalized carbon nanotube, multi-walled carbon nanotube,
activated carbon, activated carbon sphere, graphene, and
combinations thereof, wherein the at least one nanoparticle has a
particle size in the range of 30 to 500 nm; (b) at least one alkali
metal salt; and (c) a metal salt having water of crystallization,
wherein the composition has a melting temperature in the range of
100 to 150.degree. C.
[0031] In one implementation, the composition includes: (a) 0.01 to
1 wt % at least one nanoparticle selected from the group consisting
of molybdenum disulfide, cupric oxide, carbon nanotube,
functionalized carbon nanotube, multi-walled carbon nanotube,
activated carbon, activated carbon sphere, graphene, and
combinations thereof, wherein the at least one nanoparticle has a
particle size in the range of 30 to 500 nm; (b) at least one alkali
metal salt; and (c) a metal salt having water of crystallization,
wherein the composition has a melting temperature in the range of
100 to 150.degree. C.
[0032] In one implementation, the composition includes: (a) 0.01 to
0.9 wt % at least one nanoparticle selected from the group
consisting of molybdenum disulfide, cupric oxide, carbon nanotube,
functionalized carbon nanotube, multi-walled carbon nanotube,
activated carbon, activated carbon sphere, graphene, and
combinations thereof, wherein the at least one nanoparticle has a
particle size in the range of 30 to 500 nm; (b) at least one alkali
metal salt; and (c) a metal salt having water of crystallization,
wherein the composition has a melting temperature in the range of
100 to 150.degree. C.
[0033] In one implementation, the composition includes: (a) 0.01 to
0.5 wt % at least one nanoparticle selected from the group
consisting of molybdenum disulfide, cupric oxide, carbon nanotube,
functionalized carbon nanotube, multi-walled carbon nanotube,
activated carbon, activated carbon sphere, graphene, and
combinations thereof, wherein the at least one nanoparticle has a
particle size in the range of 30 to 500 nm; (b) at least one alkali
metal salt; and (c) a metal salt having water of crystallization,
wherein the composition has a melting temperature in the range of
100 to 150.degree. C.
[0034] In another implementation, the composition includes: (a) at
least one nanoparticle; (b) at least one alkali metal salt selected
from the group consisting of lithium metal salt, potassium metal
salt, and combinations thereof; and (c) a metal salt having water
of crystallization, wherein the composition has a melting
temperature in the range of 100 to 150.degree. C.
[0035] In one implementation, the composition includes: (a) at
least one nanoparticle; (b) at least one alkali metal salt selected
from the group consisting of lithium salt of inorganic anions,
sodium salt of inorganic anions, potassium salt of inorganic
anions, and combinations thereof;
[0036] and (c) a metal salt having water of crystallization,
wherein the composition has a melting temperature in the range of
range of 100 to 150.degree. C.
[0037] In another implementation, the composition includes: (a) at
least one nanoparticle; (b) 5 to 90 wt % at least one alkali metal
salt selected from the group consisting of lithium metal salt,
potassium metal salt, and combinations thereof; and (c) a metal
salt having water of crystallization, wherein the composition has a
melting temperature in the range of 100 to 150.degree. C.
[0038] In one implementation, the composition includes: (a) at
least one nanoparticle; (b) 5 to 90 wt % at least one alkali metal
salt selected from the group consisting of lithium salt of
inorganic anions, sodium salt of inorganic anions, potassium salt
of inorganic anions, and combinations thereof; and (c) a metal salt
having water of crystallization, wherein the composition has a
melting temperature in the range of range of 100 to 150.degree.
C.
[0039] In yet another implementation, the composition includes: (a)
at least one nanoparticle; (b) at least one alkali metal salt,
wherein the at least one alkali metal salt is a combination of
lithium and potassium nitrate; and (c) a metal salt having water of
crystallization, wherein the composition has a melting temperature
in the range of range of 100 to 150.degree. C.
[0040] In yet another implementation, the composition includes: (a)
at least one nanoparticle; (b) at least one alkali metal salt,
wherein the at least one alkali metal salt is a combination of 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate; and
(c) a metal salt having water of crystallization, wherein the
composition has a melting temperature in the range of range of 100
to 150.degree. C.
[0041] In yet another implementation, the composition includes: (a)
at least one nanoparticle; (b) at least one alkali metal salt; and
(c) a metal salt having water of crystallization selected from the
group consisting of alkali metal salt, alkaline earth metal salt,
and transition metal salt, wherein the composition has a melting
temperature in the range of 100 to 150.degree. C.
[0042] In yet another implementation, the composition includes: (a)
at least one nanoparticle; (b) at least one alkali metal salt; and
(c) 10 to 35 wt % metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt, wherein the
composition has a melting temperature in the range of 100 to
150.degree. C.
[0043] In yet another implementation, the composition includes: (a)
at least one nanoparticle; (b) at least one alkali metal salt; and
(c) a metal salt having water of crystallization, wherein the metal
salt is 10 to 35 wt % hydrated calcium carbonate, wherein the
composition has a melting temperature in the range of 100 to
150.degree. C.
[0044] In yet another implementation, the composition includes: (a)
0.01 to 2 wt % of molybdenum disulfide; (b) a combination of 60 to
70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate; and (c)
10 to 35 wt % hydrated calcium carbonate, wherein the composition
has a melting temperature in the range of 100 to 150.degree. C.
[0045] In yet another implementation, the composition includes: (a)
0.01 to 1 wt % of molybdenum disulfide; (b) a combination of 60 to
70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate; and (c)
10 to 35 wt % hydrated calcium carbonate, wherein the composition
has a melting temperature in the range of 100 to 150.degree. C.
[0046] In yet another implementation, the composition includes: (a)
0.01 to 0.9 wt % of molybdenum disulfide; (b) a combination of 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate; and
(c) 10 to 35 wt % hydrated calcium carbonate, wherein the
composition has a melting temperature in the range of 100 to
150.degree. C.
[0047] In yet another implementation, the composition includes: (a)
0.01 to 0.5 wt % of molybdenum disulfide; (b) a combination of 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate; and
(c) 10 to 35 wt % hydrated calcium carbonate, wherein the
composition has a melting temperature in the range of 100 to
150.degree. C.
[0048] In yet another implementation, the composition includes: (a)
0.01 to 2 wt % of cupric oxide; (b) a combination of 60 to 70 wt %
potassium nitrate and 5 to 20 wt % lithium nitrate; and (c) 10 to
35 wt % hydrated calcium carbonate, wherein the composition has a
melting temperature in the range of 100 to 150.degree. C.
[0049] In yet another implementation, the composition includes: (a)
0.01 to 2 wt % of carbon nanotubes; (b) a combination of 60 to 70
wt % potassium nitrate and 5 to 20 wt % lithium nitrate; and (c) 10
to 35 wt % hydrated calcium carbonate, wherein the composition has
a melting temperature in the range of 100 to 150.degree. C.
[0050] In yet another implementation, the composition includes: (a)
0.01 to 2 wt % of functionalized carbon nanotubes; (b) a
combination of 60 to 70 wt % potassium nitrate and 5 to 20 wt %
lithium nitrate; and (c) 10 to 35 wt % hydrated calcium carbonate,
wherein the composition has a melting temperature in the range of
100 to 150.degree. C.
[0051] In yet another implementation, the composition includes: (a)
0.01 to 2 wt % of multi-walled carbon nanotubes; (b) a combination
of 60 to 70 wt % potassium nitrate and 5 to 20 wt % lithium
nitrate; and (c) 10 to 35 wt % hydrated calcium carbonate, wherein
the composition has a melting temperature in the range of 100 to
150.degree. C.
[0052] In yet another implementation, the composition includes: (a)
0.01 to 2 wt % of activated carbon; (b) a combination of 60 to 70
wt % potassium nitrate and 5 to 20 wt % lithium nitrate;
[0053] and (c) 10 to 35 wt % hydrated calcium carbonate, wherein
the composition has a melting temperature in the range of 100 to
150.degree. C.
[0054] In yet another implementation, the composition includes: (a)
0.01 to 2 wt % of activated carbon spheres; (b) a combination of 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate; and
(c) 10 to 35 wt % hydrated calcium carbonate, wherein the
composition has a melting temperature in the range of 100 to
150.degree. C.
[0055] In yet another implementation, the composition includes: (a)
0.01 to 2 wt % of graphene; (b) a combination of 60 to 70 wt %
potassium nitrate and 5 to 20 wt % lithium nitrate; and (c) 10 to
35 wt % hydrated calcium carbonate, wherein the composition has a
melting temperature in the range of 100 to 150.degree. C.
[0056] As described above, the present disclosure relates to a
method for preparation of a composition. In one implementation, the
method for preparation of a composition includes the steps of: (a)
contacting at least one nanoparticle with at least one alkali metal
salt and a metal salt having water of crystallization to obtain a
mixture; (b) subjecting the mixture to a temperature of in the
range of 100 to 200.degree. C. in a closed system to obtain a
mixture of salts containing dispersed nanoparticles; and (d)
removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition.
[0057] In one implementation, the method for preparation of a
composition includes the steps of: (a) contacting at least one
nanoparticle selected from the group consisting of molybdenum
disulfide, cupric oxide, carbon nanotube, functionalized carbon
nanotube, multi-walled carbon nanotube, activated carbon, activated
carbon sphere, graphene, and combinations thereof with at least one
alkali metal salt and a metal salt having water of crystallization
to obtain a mixture; (b) subjecting the mixture to a temperature of
in the range of 100 to 200.degree. C. in a closed system to obtain
a mixture of salts containing dispersed nanoparticles; and (c)
removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition.
[0058] In one implementation, the method for preparation of a
composition includes the steps of: (a) contacting 0.01 to 2 wt % at
least one nanoparticle with at least one alkali metal salt and a
metal salt having water of crystallization to obtain a mixture; (b)
subjecting the mixture to a temperature of in the range of 100 to
200.degree. C. in a closed system to obtain a mixture of salts
containing dispersed nanoparticles; and (c) removing water from the
mixture of salts containing dispersed nanoparticles to obtain the
composition.
[0059] In one implementation, the method for preparation of a
composition includes the steps of: (a) contacting 0.01 to 1 wt % at
least one nanoparticle with at least one alkali metal salt and a
metal salt having water of crystallization to obtain a mixture; (b)
subjecting the mixture to a temperature of in the range of 100 to
200.degree. C. in a closed system to obtain a mixture of salts
containing dispersed nanoparticles; and (c) removing water from the
mixture of salts containing dispersed nanoparticles to obtain the
composition.
[0060] In one implementation, the method for preparation of a
composition includes the steps of: (a) contacting 0.01 to 0.9 wt %
at least one nanoparticle with at least one alkali metal salt and a
metal salt having water of crystallization to obtain a mixture; (b)
subjecting the mixture to a temperature of in the range of 100 to
200.degree. C. in a closed system to obtain a mixture of salts
containing dispersed nanoparticles; and (c) removing water from the
mixture of salts containing dispersed nanoparticles to obtain the
composition.
[0061] In one implementation, the method for preparation of a
composition includes the steps of: (a) contacting 0.01 to 0.5 wt %
at least one nanoparticle with at least one alkali metal salt and a
metal salt having water of crystallization to obtain a mixture; (b)
subjecting the mixture to a temperature of in the range of 100 to
200.degree. C. in a closed system to obtain a mixture of salts
containing dispersed nanoparticles; and (c) removing water from the
mixture of salts containing dispersed nanoparticles to obtain the
composition.
[0062] In one implementation, the method for preparation of a
composition includes the steps of: (a) contacting at least one
nanoparticle with at least one alkali metal salt selected from the
group consisting of lithium metal salt, sodium metal salt,
potassium metal salt, and combinations thereof and a metal salt
having water of crystallization to obtain a mixture; (b) subjecting
the mixture to a temperature of in the range of 100 to 200.degree.
C. in a closed system to obtain a mixture of salts containing
dispersed nanoparticles; and (c) removing water from the mixture of
salts containing dispersed nanoparticles to obtain the
composition.
[0063] In one implementation, the method for preparation of a
composition includes the steps of: (a) contacting at least one
nanoparticle with at least one alkali metal salt selected from the
group consisting of lithium salt of inorganic anions, sodium salt
of inorganic anions, potassium salt of inorganic anions, and
combinations thereof and a metal salt having water of
crystallization to obtain a mixture; (b) subjecting the mixture to
a temperature of in the range of 100 to 200.degree. C. in a closed
system to obtain a mixture of salts containing dispersed
nanoparticles; and (c) removing water from the mixture of salts
containing dispersed nanoparticles to obtain the composition.
[0064] In one implementation, the method for preparation of a
composition includes the steps of: (a) contacting at least one
nanoparticle with at least one alkali metal salt and a metal salt
having water of crystallization to obtain a mixture; (b) subjecting
the mixture to a temperature of in the range of 100 to 200.degree.
C. in a closed system to obtain a mixture of salts containing
dispersed nanoparticles; and (c) removing water from the mixture of
salts containing dispersed nanoparticles to obtain the composition,
wherein the at least one alkali metal salt weight percentage in the
composition is in the range of 5 to 90%.
[0065] In one implementation, the method for preparation of a
composition includes the steps of: (a) contacting at least one
nanoparticle with at least one alkali metal salt and a metal salt
having water of crystallization to obtain a mixture, wherein the at
least one alkali metal salt is a combination of lithium and
potassium nitrate; (b) subjecting the mixture to a temperature of
in the range of 100 to 200.degree. C. in a closed system to obtain
a mixture of salts containing dispersed nanoparticles; and (c)
removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition.
[0066] In one implementation, the method for preparation of a
composition includes the steps of: (a) contacting at least one
nanoparticle with at least one alkali metal salt and a metal salt
having water of crystallization to obtain a mixture, wherein the at
least one alkali metal salt is a combination of lithium and
potassium nitrate; (b) subjecting the mixture to a temperature of
in the range of 100 to 200.degree. C. in a closed system to obtain
a mixture of salts containing dispersed nanoparticles; and (c)
removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition, wherein potassium nitrate
weight ratio in the composition is in the range of 60 to 70% and
lithium nitrate weight percentage in the composition is in the
range of 5 to 20%.
[0067] In one implementation, the method for preparation of a
composition includes the steps of: (a) contacting at least one
nanoparticle with at least one alkali metal salt and a metal salt
having water of crystallization selected from the group consisting
of alkali metal salt, alkaline earth metal salt, and transition
metal salt to obtain a mixture; (b) subjecting the mixture to a
temperature of in the range of 100 to 200.degree. C. in a closed
system to obtain a mixture of salts containing dispersed
nanoparticles; and (c) removing water from the mixture of salts
containing dispersed nanoparticles to obtain the composition.
[0068] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting at least one
nanoparticle with at least one alkali metal salt and a metal salt
having water of crystallization and melting point in the range of
100 to 150.degree. C. to obtain a mixture; (b) subjecting the
mixture to a temperature of in the range of 100 to 200.degree. C.
in a closed system to obtain a mixture of salts containing
dispersed nanoparticles; and (c) removing water from the mixture of
salts containing dispersed nanoparticles to obtain the
composition.
[0069] In one implementation, the method for preparation of a
composition includes the steps of: (a) contacting at least one
nanoparticle with at least one alkali metal salt and a metal salt
having water of crystallization to obtain a mixture; (b) subjecting
the mixture to a temperature of in the range of 100 to 200.degree.
C. in a closed system to obtain a mixture of salts containing
dispersed nanoparticles; and (c) removing water from the mixture of
salts containing dispersed nanoparticles to obtain the composition,
wherein the metal salt having water of crystallization weight
percentage in the composition is in the range of 10 to 35%.
[0070] In one implementation, the method for preparation of a
composition includes the steps of: (a) contacting at least one
nanoparticle with at least one alkali metal salt and a metal salt
having water of crystallization to obtain a mixture; (b) subjecting
the mixture to a temperature of in the range of 100 to 200.degree.
C. in a closed system to obtain a mixture of salts containing
dispersed nanoparticles; and (c) removing water from the mixture of
salts containing dispersed nanoparticles to obtain the composition,
wherein the composition has a moisture content in the range3 to 13
wt %.
[0071] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting at least one
nanoparticle with at least one alkali metal salt and a metal salt
having water of crystallization to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. for 0.5 to 2
h in a closed system to obtain a mixture of salts containing
dispersed nanoparticles; and (c) removing water from the mixture of
salts containing dispersed nanoparticles to obtain the
composition.
[0072] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting at least one
nanoparticle with at least one alkali metal salt and a metal salt
having water of crystallization to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a closed
system at a pressure in the range of 1.0 to 3 bars to obtain a
mixture of salts containing dispersed nanoparticles; and (c)
removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition.
[0073] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting at least one
nanoparticle with at least one alkali metal salt and a metal salt
having water of crystallization to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a closed
system to obtain a mixture of salts containing dispersed
nanoparticles; and (c) removing water from the mixture of salts
containing dispersed nanoparticles to obtain the composition,
wherein the composition has a melting temperature in the range of
100 to 150.degree. C.
[0074] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-2 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof having
a particle size of 30-500 nm with 60 to 70 wt % potassium nitrate
and 5 to 20 wt % lithium nitrate and 10 to 35 wt % of a metal salt
having water of crystallization selected from the group consisting
of alkali metal salt, alkaline earth metal salt, and transition
metal salt to obtain a mixture; (b) subjecting the mixture to a
temperature of 100 to 200.degree. C. in a closed system to obtain a
mixture of salts containing dispersed nanoparticles; and (c)
removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition.
[0075] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-1 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof having
a particle size of 30-500 nm with 60 to 70 wt % potassium nitrate
and 5 to 20 wt % lithium nitrate and 10 to 35 wt % of a metal salt
having water of crystallization selected from the group consisting
of alkali metal salt, alkaline earth metal salt, and transition
metal salt to obtain a mixture; (b) subjecting the mixture to a
temperature of 100 to 200.degree. C. in a closed system to obtain a
mixture of salts containing dispersed nanoparticles; and (c)
removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition.
[0076] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-0.9 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof having
a particle size of 30-500 nm with 60 to 70 wt % potassium nitrate
and 5 to 20 wt % lithium nitrate and 10 to 35 wt % of a metal salt
having water of crystallization selected from the group consisting
of alkali metal salt, alkaline earth metal salt, and transition
metal salt to obtain a mixture; (b) subjecting the mixture to a
temperature of 100 to 200.degree. C. in a closed system to obtain a
mixture of salts containing dispersed nanoparticles; and (c)
removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition.
[0077] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-0.5 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof having
a particle size of 30-500 nm with 60 to 70 wt % potassium nitrate
and 5 to 20 wt % lithium nitrate and 10 to 35 wt % of a metal salt
having water of crystallization selected from the group consisting
of alkali metal salt, alkaline earth metal salt, and transition
metal salt to obtain a mixture; (b) subjecting the mixture to a
temperature of 100 to 200.degree. C. in a closed system to obtain a
mixture of salts containing dispersed nanoparticles; and (c)
removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition.
[0078] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-2 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a closed
system to obtain a mixture of salts containing dispersed
nanoparticles; and (c) removing water from the mixture of salts
containing dispersed nanoparticles to obtain the composition.
[0079] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-1 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a closed
system to obtain a mixture of salts containing dispersed
nanoparticles; and (c) removing water from the mixture of salts
containing dispersed nanoparticles to obtain the composition.
[0080] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-0.9 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a closed
system to obtain a mixture of salts containing dispersed
nanoparticles; and (c) removing water from the mixture of salts
containing dispersed nanoparticles to obtain the composition.
[0081] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-0.5 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a closed
system to obtain a mixture of salts containing dispersed
nanoparticles; and (c) removing water from the mixture of salts
containing dispersed nanoparticles to obtain the composition.
[0082] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-2 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h to obtain a mixture of salts containing
dispersed nanoparticles; and (c) removing water from the mixture of
salts containing dispersed nanoparticles to obtain the
composition.
[0083] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-1 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h to obtain a mixture of salts containing
dispersed nanoparticles; and (c) removing water from the mixture of
salts containing dispersed nanoparticles to obtain the
composition.
[0084] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-0.9 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h to obtain a mixture of salts containing
dispersed nanoparticles; and (c) removing water from the mixture of
salts containing dispersed nanoparticles to obtain the
composition.
[0085] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-0.5 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h to obtain a mixture of salts containing
dispersed nanoparticles; and (c) removing water from the mixture of
salts containing dispersed nanoparticles to obtain the
composition.
[0086] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-2 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h at a pressure in the range of 1.3 to 3 to
obtain a mixture of salts containing dispersed nanoparticles; and
(c) removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition.
[0087] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-1 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h at a pressure in the range of 1.3 to 3 to
obtain a mixture of salts containing dispersed nanoparticles; and
(c) removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition.
[0088] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-0.9 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h at a pressure in the range of 1.3 to 3 to
obtain a mixture of salts containing dispersed nanoparticles; and
(c) removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition.
[0089] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-0.5 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h at a pressure in the range of 1.3 to 3 to
obtain a mixture of salts containing dispersed nanoparticles; and
(c) removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition.
[0090] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-2 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h at a pressure in the range of 1.3 to 3 bars to
obtain a mixture of salts containing dispersed nanoparticles; and
(c) removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition, wherein the mixture has a
moisture content in the range 3 to 13 wt %.
[0091] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-1 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h at a pressure in the range of 1.3 to 3 bars to
obtain a mixture of salts containing dispersed nanoparticles; and
(c) removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition, wherein the mixture has a
moisture content in the range 3 to 13 wt %.
[0092] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-0.9 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h at a pressure in the range of 1.3 to 3 bars to
obtain a mixture of salts containing dispersed nanoparticles; and
(c) removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition, wherein the mixture has a
moisture content in the range 3 to 13 wt %.
[0093] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-0.5 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h at a pressure in the range of 1.3 to 3 bars to
obtain a mixture of salts containing dispersed nanoparticles; and
(c) removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition, wherein the mixture has a
moisture content in the range 3 to 13 wt %.
[0094] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-2 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h at a pressure in the range of 1.3 to 3 bars to
obtain a mixture of salts containing dispersed nanoparticles; and
(c) removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition, wherein the mixture has a
moisture content in the range 3 to 13 wt %, and wherein the mixture
has a melting temperature in the range of 100 to 150.degree. C.
[0095] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-1 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h at a pressure in the range of 1.3 to 3 bars to
obtain a mixture of salts containing dispersed nanoparticles; and
(c) removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition, wherein the mixture has a
moisture content in the range 3 to 13 wt %, and wherein the mixture
has a melting temperature in the range of 100 to 150.degree. C.
[0096] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-0.9 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h at a pressure in the range of 1.3 to 3 bars to
obtain a mixture of salts containing dispersed nanoparticles; and
(c) removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition, wherein the mixture has a
moisture content in the range 3 to 13 wt %, and wherein the mixture
has a melting temperature in the range of 100 to 150.degree. C.
[0097] In one implementation, the method for preparation of
composition includes the steps of: (a) contacting 0.01-0.5 wt % at
least one nanoparticle selected from the group consisting of
molybdenum disulfide, cupric oxide, carbon nanotube, functionalized
carbon nanotube, multi-walled carbon nanotube, activated carbon,
activated carbon sphere, graphene, and combinations thereof with 60
to 70 wt % potassium nitrate and 5 to 20 wt % lithium nitrate and
10 to 35 wt % of a metal salt having water of crystallization
selected from the group consisting of alkali metal salt, alkaline
earth metal salt, and transition metal salt with a melting point in
the range 40 to 120.degree. C. to obtain a mixture; (b) subjecting
the mixture to a temperature of 100 to 200.degree. C. in a pressure
tube for 0.5 to 2 h at a pressure in the range of 1.3 to 3 bars to
obtain a mixture of salts containing dispersed nanoparticles; and
(c) removing water from the mixture of salts containing dispersed
nanoparticles to obtain the composition, wherein the mixture has a
moisture content in the range 3 to 13 wt %, and wherein the mixture
has a melting temperature in the range of 100 to 150.degree. C.
EXAMPLES
[0098] The disclosure will now be illustrated with working
examples, which is intended to illustrate the working of disclosure
and not intended to take restrictively to imply any limitations on
the scope of the present disclosure. Other examples are also
possible which are within the scope of the present disclosure.
[0099] The melting points and enthalpies of compositions comprising
of salt mixture and nanoparticles were measured using differential
scanning calorimetry (DSC). Mass changes with respect to
temperature in different gas atmospheres were measured using
thermogravimetric analysis (TGA). Both DSC and TGA were determined
simultaneously using NETZCH Simultaneous Thermal Analyzer STA 449
F3 Jupiter. The TGA-DSC analysis has been determined both in
nitrogen atmosphere as well as air atmosphere.
[0100] Specific heat capacity was measured using DSC technique. For
specific heat measurements three measurements have been done; first
a correction run using empty crucibles, second using the first
correction run, done the measurement using sapphire disc as
standard, third the DSC measurement uses the sample. Finally, after
the three measurements, the specific heat capacities of samples
with respect to temperature have been measured using ratio
method.
[0101] Thermal conductivity was determined by using transient plane
source method and the instrument used was HOT-DISK TPS 2500 S
thermal conductivity meter. The molten salt powder was put in a
small metal cup (made up of non-corrosive Inconel) and placed with
the HOT DISK sensor, named 5465 (radius 3.189 mm) in the furnace.
The furnace was put on end, so that the furnace tube is vertical,
not horizontal as commonly used. This way the sample could melt to
liquid and still stay within the cup. The closed furnace was
evacuated and filled with N.sub.2 to protect from any air or
moisture.
[0102] The temperature was then raised to 250.degree. C., kept
stable for a while, so that all materials melt. Then during the
natural cooling of the furnace, when target temperature was set to
RT, one reading at each 30 min interval was taken. This gave a
series of measurements from 245.degree. C. to 32 .degree. C. Each
measurement was evaluated with temperature drift compensation, but
since the cooling rate was so slow and steadily progressing, it did
not cause any noise in the results. Thermal conductivities of
HPHTF-A, HPHTF-A+0.5 wt % MoS.sub.2 at 200.degree. C. are 0.5063
and 0.5921 W/mK respectively.
Example 1
Synthesis of Nanoparticles
[0103] The MoS.sub.2 nanoparticles were synthesized as described in
the literature (Yumei Tian et al., Materials Letters, 2006, 60
527-529) and CuO nanoparticles were synthesized as described by R.
Etefagh et al. (Scientia Iranica, Transactions F: Nanotechnology,
2013, 20, 1055-1058). Activated charcoal was purchased from MERCK
and activated carbon spheres also collected from commercial
sources. Carbon nanotubes were received from commercial sources and
acid functionalization has been done as follows. In a 500 mL round
bottom flask, 500 mg of multi-walled CNT was taken and 150 mL of a
mixture of concentrated H.sub.2SO.sub.4 and concentrated HNO.sub.3
(3:1 ratio) was added and sonicated for 6 h at 70.degree. C. After
the reaction the reaction mixture was diluted by distilled water
and filtered. The filter cake is dried at 120.degree. C. overnight
to get acid-functionalized CNT.
Synthesis of the Composition Comprising of Molten Salt Mixture and
Dispersed Nanoparticles
[0104] Metals salts, such as KNO.sub.3, (60 to 70 Wt %), LiNO.sub.3
(5 to 20 Wt %), the hydrated salt (10 to 30 Wt %), and
nanoparticles (0.01 to 2 wt %) were weighed according to the
composition provided in Table 1 and mixed in a pressure tube with
magnetic pellet to form a mixture of salts containing uniformly
dispersed nanoparticles. The pressure tube was tightened with
Teflon screw, and heated at 200.degree. C. and stirred using a
magnetic stirrer associated with in-built oil bath. After evolution
of hydrated water, the salts were dissolved internally and the
nanoparticles were dispersed uniformly in the mixture. The solution
was thoroughly mixed and kept at 200.degree. C. for 2 hours and
then the pressure was released by opening the tube and water
removed using rotary evaporator. The pressure inside the tube was
measured using pressure gauge found to be in the range of 1.2 to 3
bar. The melting points of the compositions are provided in Table 1
and are below 150.degree. C. The water content of the whole mixture
can be calculated using TGA analysis. The moisture content of the
composition was found to be in the range of 3 to 13 wt %.
TABLE-US-00001 TABLE 1 Compositions comprising salt mixture and
dispersed nanoparticles Particle Melting Wt ratio size of point of
Wt ratio of nanoparticles Compositions Materials Salts in pressure
tube of salts nanoparticles (nm) (.degree. C.) HPHTF-A +
KNO3:Ca(NO.sub.3).sub.2.cndot.4H.sub.2O:LiNO3 66.6:18.9:13.9 0.49
200 137.2 MoS.sub.2 nanoparticles HPHTF-A +
KNO3:Ca(NO.sub.3).sub.2.cndot.4H.sub.2O:LiNO3 66.3:18.8:13.8 0.99
200 137.4 1.0 MoS.sub.2 HPHTF-A +
KNO3:Ca(NO.sub.3).sub.2.cndot.4H.sub.2O:LiNO3 65.6:18.6:13.7 1.96
200 135.9 2.0 MoS.sub.2
[0105] FIG. 1 shows scanning electron microscopy (SEM) images of
HPHTF-A and nanoparticle incorporated salt in different
compositions (A) Pure HPHTF-A, (B) HPHTF-A+0.5 wt % MoS.sub.2, (C)
HPHTF-A+1.0 wt % MoS.sub.2, (D) HPHTF-A+2.0 wt % MoS.sub.2. SEM
images were taken using ZEISS FE-SEM Sigma instrument. As seen in
FIG. 1(A), nanoparticles are uniformly dispersed in molten salt
mixture and less agglomeration is observed when 0.5 wt % of
nanoparticles is used in the composition. However, when weight
percentage of nanoparticles is increased in the composition of the
present disclosure, nanoparticles tend to form clusters in the
molten salt mixture as seen in FIGS. 1(B) and 1(C).
[0106] FIG. 2 shows TGA and DSC of MoS.sub.2 nanoparticle under
Nitrogen atmosphere. The MoS.sub.2 nanoparticles were heated from
RT to 1000.degree. C. at a heating rate of 10.degree. C./min,
nitrogen purge flow was 80 mL/min. MoS.sub.2 nanoparticles used for
adding to the molten salt mixture are stable up to 400.degree.
C.
[0107] FIG. 3 shows carbon-sulfur analysis plot of synthesized MoS2
nanoparticles. Molecular weight of MoS.sub.2 is 160 and that of
Sulfur is 32. So theoretical value of Sulfur content is 40% and
obtained value is 43%, which indicates that the MoS.sub.2
nanoparticles have been successfully synthesized.
[0108] FIG. 4 shows TGA and DSC of CuO nanoparticle under Nitrogen
atmosphere. The CuO nanoparticles were heated from RT to
1000.degree. C. at a heating rate of 10.degree. C./min, nitrogen
purge flow was 80 mL/min CuO nanoparticles used for adding to the
molten salt mixture are stable up to 400.degree. C.
[0109] FIG. 5 shows TGA and DSC of carbon nanotube (CNT)
nanoparticle under Nitrogen atmosphere. The CuO nanoparticles were
heated from RT to 1000.degree. C. at a heating rate of 10.degree.
C./min, nitrogen purge flow was 80 mL/min. CNT nanoparticles used
for adding to the molten salt mixture are stable up to 450.degree.
C.
[0110] FIG. 6 shows TGA and DSC of HPHTF-A+0.5 wt % MoS.sub.2 under
Nitrogen atmosphere and Air atmosphere. The aforementioned sample
was heated from RT to 1000.degree. C. at a heating rate of
10.degree. C./min; nitrogen/air purge flow was 80 mL/min. TGA in
different atmospheres (N2 and Air) showed that the sample is
thermally stable up to 560.degree. C. Endothermic peaks at 134.2,
and 137.2.degree. C. denotes the melting points of HPHTF-A+0.5 wt %
MoS.sub.2 in air and nitrogen atmosphere respectively. Melting
point of pure HPHTF-A was 137.degree. C. which got increased to
137.2.degree. C. the in nitrogen atmosphere after addition of
nanoparticle (0.5 wt % MoS2).
[0111] FIG. 7 shows TGA and DSC of HPHTF-A+1.0 wt % MoS.sub.2 under
Nitrogen atmosphere and Air atmosphere. The aforementioned sample
was heated from RT to 1000.degree. C. at a heating rate of
10.degree. C./min; nitrogen/air purge flow was 80 mL/min TGA in
different atmospheres (N.sub.2 and Air) showed that the sample is
thermally stable up to 560.degree. C. Endothermic peaks at 134.4,
and 137.4.degree. C. denotes the melting points of HPHTF-A+1.0 wt %
MoS.sub.2 in air and nitrogen atmosphere respectively. Melting
point of pure HPHTF-A was 137.degree. C. which got increased to
137.4.degree. C. the in nitrogen atmosphere after addition of
nanoparticle (1.0 wt % MoS2).
[0112] FIG. 8 shows TGA and DSC of HPHTF-A+2.0 wt % MoS.sub.2 under
Nitrogen atmosphere and Air atmosphere. The aforementioned sample
was heated from RT to 1000.degree. C. at a heating rate of
10.degree. C./min; nitrogen/air purge flow was 80 mL/min. TGA in
different atmospheres (N2 and Air) showed that the sample is
thermally stable up to 560.degree. C. Endothermic peaks at 136.4,
and 135.9.degree. C. denotes the melting points of HPHTF-A+2.0 wt %
MoS.sub.2 in air and nitrogen atmosphere respectively. Melting
point of pure HPHTF-A was 137.degree. C. which got decreased to
135.9.degree. C. the in nitrogen atmosphere after addition of
nanoparticle (2.0 wt % MoS.sub.2).
TABLE-US-00002 TABLE 2 Characteristics of compositions of the
present disclosure. Melting Thermal Cp Cp Cp Point Enthalpy
Stability (kJ/kgK) (kJ/kgK) (kJ/kgK) Materials (.degree. C.) (J/g)
(.degree. C.) @ RT @ 200.degree. C. @ 300.degree. C. HPHTF-A 137.0
5.01 ~550 1.761 1.644 2.084 HPHTF-A + 137.2 10.67 ~560 2.159 1.672
2.385 0.5 MoS.sub.2 HPHTF-A + 137.4 11.64 ~560 1.599 0.668 0.568
1.0 MoS.sub.2 HPHTF-A + 135.9 11.80 ~560 0.961 0.205 0.865 2.0
MoS.sub.2
[0113] Table 2 shows the melting point, enthalpy of fusion, thermal
stability and specific heat capacity. Specific heat capacity is
measured at room temperature, at 200.degree. C. and at 300.degree.
C. Melting point of HPHTF-A, HPHTF-A+0.5 wt % MoS.sub.2,
HPHTF-A+1.0 wt % MoS.sub.2 and HPHTF-A+2.0 wt % MoS.sub.2 is 137,
137.2, 137.4 and 135.9.degree. C. and the enthalpy of fusion is
5.01, 10.67, 11.64 and 11.80 respectively. The salts were found to
be thermally stable and can be used safely around 560.degree. C.
without any degradation. The specific heat capacity (Cp)values of
HPHTF-A+0.5% MoS.sub.2 are 2.159, 1.672 and 2.385 kJ/kgK at room
temperature (RT), at 200.degree. C., and at 300.degree. C.
respectively which is higher than the Cp values of HPHTF-A,
HPHTF-A+1.0 wt % MoS.sub.2 and HPHTF-A+2.0 wt % MoS.sub.2 given in
Table 2.
[0114] Further, thermal conductivity of HPHTF-A+0.5 wt % MoS.sub.2
is found to be more than that of pure HPHTF-A. Thermal conductivity
of pure HPHTF-A is 0.5063 W/mK at 200.degree. C. and that of
HPHTF-A+0.5 wt % MoS.sub.2 sample is 0.5921 W/mK at 200.degree.
C.
[0115] From the above data it can be inferred that these
compositions may act as more efficient solar thermal energy storage
material than the molten salt mixture alone.
Advantages Gained in the Example Illustrative Process in this
Subject Matter:
[0116] Molten salt based thermal energy storage received much
attention due to the availability and low cost of molten salt, high
thermal stability and thermal conductivity compared to the organic
based thermal storage fluids, low viscosity at high temperature
etc. However, molten salts are relatively limited in terms of their
thermal energy storage capacity. The addition of nanoparticles
improves the thermal conductivity, thermal stability, specific heat
capacity without sacrificing the heat of fusion to a large extent.
The present disclosure provides a one-pot synthesis which is easy
and cost effective where nanoparticles and salt mixtures in such a
way that one of the salts is hydrated taken in a pressure tube and
stirred at 200.degree. for 2 h. After that remove the water under
reduced pressure and the nanoparticle incorporated salt can be used
directly for heat storage as well as heat transfer applications.
The nano-molten salts obtained after optimization of nanoparticle
content showed better thermal conductivity and better specific heat
capacity compared to original molten salt.
[0117] Although the subject matter has been described in
considerable detail with reference to certain examples and
implementations thereof, other implementations are possible. As
such, the spirit and scope of the appended claims should not be
limited to the description of the preferred examples and
implementations contained therein.
* * * * *